Cruise control systems are used in motor vehicles in order to automatically regulate a target speed that has been preset by the vehicle driver as far as possible, especially on long stretches of road, so that, with the exception of any temporary braking maneuvers that must be performed, the vehicle driver only needs to make steering movements. While in classic cruise control systems, during normal operation, state variables of the respective motor vehicle are used in order to automatically adjust the speed in accordance with the respective desired speed, and in so doing, to remain within a predefined speed band, in the modern control of cruise control systems, information concerning a stretch of road ahead is also used, in part, in order to make predictive control possible. In so doing, a gradient profile for the stretch of road ahead is frequently taken into consideration in order to be able to drive incline grades in the stretch of road ahead in an optimal manner, in particular with respect to economic and ecological factors, in the course of automatic speed control.
A method for predictive control of a cruise control system of a motor vehicle arises from DE 10 2009 040 682 A1. Here, roadway parameters for a stretch of road ahead, which include a gradient profile for this stretch of road ahead, inter alia, are factored in. Based on the roadway parameters as well as current vehicle parameters, a selection is then made from a variety of control variants of the cruise control system, wherein, in so doing, an approximate predictive horizon is determined, which is subsequently subdivided into segments based on the gradient. The influence of a respectively selected control variant, as well as the suitability of the variant for the need-based control of the cruise control system, is then checked for each segment for one or a plurality of applications.